This is an automated email from the git hooks/post-receive script. Git pushed a commit to branch master in repository ffmpeg. commit f570fa787a813195775521ed28bf0ff302cc93b8 Author: Andreas Rheinhardt <andreas.rheinhardt@outlook.com> AuthorDate: Tue Feb 24 16:41:07 2026 +0100 Commit: Andreas Rheinhardt <andreas.rheinhardt@outlook.com> CommitDate: Sat Feb 28 09:56:01 2026 +0100 swscale/swscale_internal: Move altivec parts to ppc/ Up until now, several altivec-specific fields are directly put into SwsInternal #if HAVE_ALTIVEC is true. These fields are of altivec-specific vector types and therefore require altivec specific headers to be included. Unfortunately, said altivec specific headers redefine bool in a manner that is incompatible with stdbool. swscale/ops.h uses bool and this led graph.c and ops.c to disagree about the layout of structures from ops.h, leading to heap corruption [1], [2] in the sws-unscaled FATE test. Fix this by moving the altivec-specific parts out of SwsInternal and into a structure that extends SwsInternal and is allocated jointly with it. Said structure is local to yuv2rgb_altivec.c, because this is the only file accessing said fields. Should more files need them, an altivec-specific swscale header would need to be added. Thanks to jfiusdq <jfiusdq@proton.me> for analyzing the issue. [1]: https://fate.ffmpeg.org/report.cgi?slot=ppc64-linux-gcc-14.3-asan&time=20260224065643 [2]: https://fate.ffmpeg.org/report.cgi?slot=ppc64-linux-gcc-14.3&time=20260224051615 Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com> --- libswscale/ppc/yuv2rgb_altivec.c | 100 ++++++++++++++++++++++++++------------- libswscale/ppc/yuv2yuv_altivec.c | 1 + libswscale/swscale_internal.h | 19 +++----- libswscale/utils.c | 2 +- 4 files changed, 76 insertions(+), 46 deletions(-) diff --git a/libswscale/ppc/yuv2rgb_altivec.c b/libswscale/ppc/yuv2rgb_altivec.c index 3efb33d22e..cad3f8d7c0 100644 --- a/libswscale/ppc/yuv2rgb_altivec.c +++ b/libswscale/ppc/yuv2rgb_altivec.c @@ -103,6 +103,34 @@ #include "yuv2rgb_altivec.h" #if HAVE_ALTIVEC +// util_altivec.h includes the system header altivec.h which redefines bool, +// making it incompatible with stdbool.h. It therefore must not be included +// before another one of our headers that may use bool. +#include "libavutil/ppc/util_altivec.h" +#include <assert.h> + +typedef struct SwsInternalAltivec { + SwsInternal c; + + vector signed short CY; + vector signed short CRV; + vector signed short CBU; + vector signed short CGU; + vector signed short CGV; + vector signed short OY; + vector unsigned short CSHIFT; + vector signed short *vYCoeffsBank, *vCCoeffsBank; +} SwsInternalAltivec; +// Check that the sizes of the types match. +// Note that given that SwsInternal is always allocated via av_malloc, +// every pointer to an SwsInternal is always sufficiently aligned. +static_assert(sizeof(SwsInternalAltivec) <= sizeof(SwsInternal) + SWSINTERNAL_ADDITIONAL_ASM_SIZE, + "SWSINTERNAL_ADDITIONAL_ASM_SIZE needs to be increased"); + +static inline SwsInternalAltivec *sws_internal_altivec(SwsInternal *c) +{ + return (SwsInternalAltivec*)c; +} #undef PROFILE_THE_BEAST #undef INC_SCALING @@ -259,25 +287,26 @@ static inline void cvtyuvtoRGB(SwsInternal *c, vector signed short Y, vector signed short *R, vector signed short *G, vector signed short *B) { + SwsInternalAltivec *const a = sws_internal_altivec(c); vector signed short vx, ux, uvx; - Y = vec_mradds(Y, c->CY, c->OY); + Y = vec_mradds(Y, a->CY, a->OY); U = vec_sub(U, (vector signed short) vec_splat((vector signed short) { 128 }, 0)); V = vec_sub(V, (vector signed short) vec_splat((vector signed short) { 128 }, 0)); - // ux = (CBU * (u << c->CSHIFT) + 0x4000) >> 15; - ux = vec_sl(U, c->CSHIFT); - *B = vec_mradds(ux, c->CBU, Y); + // ux = (CBU * (u << a->CSHIFT) + 0x4000) >> 15; + ux = vec_sl(U, a->CSHIFT); + *B = vec_mradds(ux, a->CBU, Y); - // vx = (CRV * (v << c->CSHIFT) + 0x4000) >> 15; - vx = vec_sl(V, c->CSHIFT); - *R = vec_mradds(vx, c->CRV, Y); + // vx = (CRV * (v << a->CSHIFT) + 0x4000) >> 15; + vx = vec_sl(V, a->CSHIFT); + *R = vec_mradds(vx, a->CRV, Y); // uvx = ((CGU * u) + (CGV * v)) >> 15; - uvx = vec_mradds(U, c->CGU, Y); - *G = vec_mradds(V, c->CGV, uvx); + uvx = vec_mradds(U, a->CGU, Y); + *G = vec_mradds(V, a->CGV, uvx); } /* @@ -301,6 +330,7 @@ static int altivec_ ## name(SwsInternal *c, const unsigned char *const *in, \ const int *instrides, int srcSliceY, int srcSliceH, \ unsigned char *const *oplanes, const int *outstrides) \ { \ + SwsInternalAltivec *const a = sws_internal_altivec(c); \ int w = c->opts.src_w; \ int h = srcSliceH; \ int i, j; \ @@ -318,13 +348,13 @@ static int altivec_ ## name(SwsInternal *c, const unsigned char *const *in, \ vector signed short R1, G1, B1; \ vector unsigned char R, G, B; \ \ - vector signed short lCY = c->CY; \ - vector signed short lOY = c->OY; \ - vector signed short lCRV = c->CRV; \ - vector signed short lCBU = c->CBU; \ - vector signed short lCGU = c->CGU; \ - vector signed short lCGV = c->CGV; \ - vector unsigned short lCSHIFT = c->CSHIFT; \ + vector signed short lCY = a->CY; \ + vector signed short lOY = a->OY; \ + vector signed short lCRV = a->CRV; \ + vector signed short lCBU = a->CBU; \ + vector signed short lCGU = a->CGU; \ + vector signed short lCGV = a->CGV; \ + vector unsigned short lCSHIFT = a->CSHIFT; \ \ const ubyte *y1i = in[0]; \ const ubyte *y2i = in[0] + instrides[0]; \ @@ -612,6 +642,8 @@ av_cold void ff_yuv2rgb_init_tables_ppc(SwsInternal *c, int saturation) { #if HAVE_ALTIVEC + SwsInternalAltivec *const a = sws_internal_altivec(c); + union { DECLARE_ALIGNED(16, signed short, tmp)[8]; vector signed short vec; @@ -627,13 +659,13 @@ av_cold void ff_yuv2rgb_init_tables_ppc(SwsInternal *c, buf.tmp[4] = -((inv_table[2] >> 1) * (contrast >> 16) * (saturation >> 16)); // cgu buf.tmp[5] = -((inv_table[3] >> 1) * (contrast >> 16) * (saturation >> 16)); // cgv - c->CSHIFT = (vector unsigned short) vec_splat_u16(2); - c->CY = vec_splat((vector signed short) buf.vec, 0); - c->OY = vec_splat((vector signed short) buf.vec, 1); - c->CRV = vec_splat((vector signed short) buf.vec, 2); - c->CBU = vec_splat((vector signed short) buf.vec, 3); - c->CGU = vec_splat((vector signed short) buf.vec, 4); - c->CGV = vec_splat((vector signed short) buf.vec, 5); + a->CSHIFT = (vector unsigned short) vec_splat_u16(2); + a->CY = vec_splat((vector signed short) buf.vec, 0); + a->OY = vec_splat((vector signed short) buf.vec, 1); + a->CRV = vec_splat((vector signed short) buf.vec, 2); + a->CBU = vec_splat((vector signed short) buf.vec, 3); + a->CGU = vec_splat((vector signed short) buf.vec, 4); + a->CGV = vec_splat((vector signed short) buf.vec, 5); return; #endif /* HAVE_ALTIVEC */ } @@ -653,6 +685,8 @@ static av_always_inline void yuv2packedX_altivec(SwsInternal *c, int dstW, int dstY, enum AVPixelFormat target) { + SwsInternalAltivec *const a = sws_internal_altivec(c); + int i, j; vector signed short X, X0, X1, Y0, U0, V0, Y1, U1, V1, U, V; vector signed short R0, G0, B0, R1, G1, B1; @@ -666,8 +700,8 @@ static av_always_inline void yuv2packedX_altivec(SwsInternal *c, vector signed short *YCoeffs, *CCoeffs; - YCoeffs = c->vYCoeffsBank + dstY * lumFilterSize; - CCoeffs = c->vCCoeffsBank + dstY * chrFilterSize; + YCoeffs = a->vYCoeffsBank + dstY * lumFilterSize; + CCoeffs = a->vCCoeffsBank + dstY * chrFilterSize; out = (vector unsigned char *) dest; @@ -876,20 +910,21 @@ YUV2PACKEDX_WRAPPER(bgr24, AV_PIX_FMT_BGR24); av_cold int ff_sws_init_altivec_bufs(SwsInternal *c) { const SwsContext *const sws = &c->opts; + SwsInternalAltivec *const a = sws_internal_altivec(c); - c->vYCoeffsBank = av_malloc_array(sws->dst_h, c->vLumFilterSize * sizeof(*c->vYCoeffsBank)); - c->vCCoeffsBank = av_malloc_array(c->chrDstH, c->vChrFilterSize * sizeof(*c->vCCoeffsBank)); - if (!c->vYCoeffsBank || !c->vCCoeffsBank) + a->vYCoeffsBank = av_malloc_array(sws->dst_h, c->vLumFilterSize * sizeof(*a->vYCoeffsBank)); + a->vCCoeffsBank = av_malloc_array(c->chrDstH, c->vChrFilterSize * sizeof(*a->vCCoeffsBank)); + if (!a->vYCoeffsBank || !a->vCCoeffsBank) return AVERROR(ENOMEM); for (int i = 0; i < c->vLumFilterSize * sws->dst_h; ++i) { - short *p = (short *)&c->vYCoeffsBank[i]; + short *p = (short *)&a->vYCoeffsBank[i]; for (int j = 0; j < 8; ++j) p[j] = c->vLumFilter[i]; } for (int i = 0; i < c->vChrFilterSize * c->chrDstH; ++i) { - short *p = (short *)&c->vCCoeffsBank[i]; + short *p = (short *)&a->vCCoeffsBank[i]; for (int j = 0; j < 8; ++j) p[j] = c->vChrFilter[i]; } @@ -899,7 +934,8 @@ av_cold int ff_sws_init_altivec_bufs(SwsInternal *c) av_cold void ff_sws_free_altivec_bufs(SwsInternal *c) { - av_freep(&c->vYCoeffsBank); - av_freep(&c->vCCoeffsBank); + SwsInternalAltivec *const a = sws_internal_altivec(c); + av_freep(&a->vYCoeffsBank); + av_freep(&a->vCCoeffsBank); } #endif /* HAVE_ALTIVEC */ diff --git a/libswscale/ppc/yuv2yuv_altivec.c b/libswscale/ppc/yuv2yuv_altivec.c index 7884c38d69..3e3bbea23a 100644 --- a/libswscale/ppc/yuv2yuv_altivec.c +++ b/libswscale/ppc/yuv2yuv_altivec.c @@ -30,6 +30,7 @@ #include "libswscale/swscale_internal.h" #if HAVE_ALTIVEC +#include "libavutil/ppc/util_altivec.h" static int yv12toyuy2_unscaled_altivec(SwsInternal *c, const uint8_t *const src[], const int srcStride[], int srcSliceY, diff --git a/libswscale/swscale_internal.h b/libswscale/swscale_internal.h index d9fddb271b..f4007379ab 100644 --- a/libswscale/swscale_internal.h +++ b/libswscale/swscale_internal.h @@ -37,10 +37,14 @@ #include "libavutil/pixfmt.h" #include "libavutil/pixdesc.h" #include "libavutil/slicethread.h" +#include "libavutil/half2float.h" + #if HAVE_ALTIVEC -#include "libavutil/ppc/util_altivec.h" +#define SWSINTERNAL_ADDITIONAL_ASM_SIZE (7*16 + 2*8 + /* alignment */ 16) +#endif +#ifndef SWSINTERNAL_ADDITIONAL_ASM_SIZE +#define SWSINTERNAL_ADDITIONAL_ASM_SIZE 0 #endif -#include "libavutil/half2float.h" #define STR(s) AV_TOSTRING(s) // AV_STRINGIFY is too long @@ -544,17 +548,6 @@ struct SwsInternal { const uint8_t *chrDither8, *lumDither8; -#if HAVE_ALTIVEC - vector signed short CY; - vector signed short CRV; - vector signed short CBU; - vector signed short CGU; - vector signed short CGV; - vector signed short OY; - vector unsigned short CSHIFT; - vector signed short *vYCoeffsBank, *vCCoeffsBank; -#endif - int use_mmx_vfilter; /* pre defined color-spaces gamma */ diff --git a/libswscale/utils.c b/libswscale/utils.c index 4e6e503b75..90839817d8 100644 --- a/libswscale/utils.c +++ b/libswscale/utils.c @@ -1031,7 +1031,7 @@ int sws_getColorspaceDetails(SwsContext *sws, int **inv_table, SwsContext *sws_alloc_context(void) { - SwsInternal *c = (SwsInternal *) av_mallocz(sizeof(SwsInternal)); + SwsInternal *c = av_mallocz(sizeof(*c) + SWSINTERNAL_ADDITIONAL_ASM_SIZE); if (!c) return NULL;